server.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>

#include <sys/socket.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <pthread.h>
#include "global.h"

/* 服务器ip和端口号 */
#define _addr_ "127.0.0.1"
#define _port_ 8888

typedef struct client {
    char nick[32];
    int con_fd;
}Client;

static pthread_t cli_thrd[1024];    /* 服务器并发线程 */
Client cli[1024];   /* 客户端 */
static int cli_que_len;
static char buf[MAX_BUF_LEN];

void *recv_thrd(void *arg);   /* server for client */
void remove_client(const int client_id);    /* deal with client quit */
void get_dst_nick(const char *msg, char *ret);  /* 客户与客户之间的通信 */
int client_connected(const char *nick); /* 此昵称的客户在线 */

int main(int argc, char *argv[])
{
    struct sockaddr_in srv;
    int sock_fd, chk, con_fd;
    pthread_attr_t attr;

    if ((sock_fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
    {
        printf("socket error!");
        return -1;
    }

    bzero(&srv, sizeof(srv));
    srv.sin_family = AF_INET;
    srv.sin_port = htons(_port_);

    /* inet_pton: support ipv6 and ipv4, set the ipaddr */
    if (inet_pton(AF_INET, _addr_, &srv.sin_addr) < 0)
    {
        printf("inet_pton error!");
        return -1;
    }

    chk = bind(sock_fd, (struct sockaddr*)&srv, sizeof(srv));
    if (chk < 0)
    {
        printf("bind error!");
        return -1;
    }

    chk = listen(sock_fd, MAX_LISTEN_QUEUE);
    if (chk < 0)
    {
        printf("listen error!");
        return -1;
    }

    /* 初始化线程参数 */
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);

    cli_que_len = 0;
    while (1)
    {
        con_fd = accept(sock_fd, (struct sockaddr*)NULL, NULL);
        printf("a client connected!\n");

        /* get the nickname of the client */
        cli[cli_que_len].con_fd = con_fd;
        printf("fd = %d\n", con_fd);
        strcpy(cli[cli_que_len].nick, "fuck");

        /* create server thread for a new client */
        chk = pthread_create(cli_thrd + cli_que_len, &attr, recv_thrd, cli + cli_que_len);
        if (chk)
        {
            printf("create thread error!");
            continue;
        }
        ++cli_que_len;
    }
    close(sock_fd);

    return 0;
}

void *recv_thrd(void *arg)   /* server for client */
{
    int sock_fd, dst_fd, i;
    int rec_bytes;
    Client *cli_ptr = NULL;
    char *ptr = NULL;

    cli_ptr = (Client *)arg;
    sock_fd = cli_ptr->con_fd;
    printf("thread nick: %s\nthread fd: %d\n", cli_ptr->nick, cli_ptr->con_fd);

    while ((rec_bytes = recv(sock_fd, buf, sizeof(buf), 0)) > 0)
    {
        printf("server receive(%d): %s\n", cli_ptr->con_fd, buf);
        buf[rec_bytes] = '\0';
        if (strstr(buf, "::") == NULL)  /* send to all online people */
        {
            for (i = 0; i < cli_que_len; ++i)
            {
                printf("%d: fd = %d\n", i + 1, cli[i].con_fd);
                if (cli[i].con_fd != sock_fd)
                {
                    send(cli[i].con_fd, buf, sizeof(buf), 0);
                }
            }
        }
        else
        {
            sscanf(buf, "%d", &dst_fd);
            ptr = buf;
            ptr = strstr(buf, "::");
            ptr += 2;
            for (i = 0; i < cli_que_len; ++i)
            {
                printf("%d: fd = %d\n", i + 1, cli[i].con_fd);
                if (cli[i].con_fd == dst_fd)
                {
                    send(dst_fd, ptr, sizeof(buf) - (ptr - buf), 0);
                }
            }
        }
    }

    close(sock_fd);
    remove_client(sock_fd);
    printf("a client(%d) quit!\n", cli_ptr->con_fd);

    pthread_exit(NULL);
}

void remove_client(const int client_id)    /* deal with client quit */
{
    int i, index;

    index = -1;
    for (i = 0; i < cli_que_len; ++i)
    {
        if (cli[i].con_fd == client_id)
        {
            index = i;
            break;
        }
    }

    if (index > 0)
    {
        for (i = index + 1; i < cli_que_len; ++i)
        {
            cli[i - 1].con_fd = cli[i].con_fd;
            strcpy(cli[i - 1].nick, cli[i].nick);
        }
    }
    --cli_que_len;
}

/* 此昵称的客户在线 */
int client_connected(const char *nick)
{
    int i;

    for (i = 0; i < cli_que_len; ++i)
    {
        if (strcpy(cli[i].nick, nick) == 0)
        {
            return 1;
        }
    }

    return 0;
}